■370 XVI, siROSiPHONiACE.E (West). [Stigonema 



4. S. informe Kiitz. Spec. Algar. 319 (1849) ; Tab. Phyc. ii. 

 (1850-2), 11, t. 38, fig. iii. ; Born, et Flah., I.e., 75-77 (1887) ; W. 

 et G. S. West in Journ. Bot. 1897, p. 243. 



PuNGO Andongo. — Inter Scijtonemn Mj/ochrous var. chorographicum, 

 in summis rupib. Praesidii (Pedras negras) ; Feb. 1857. No. 6. 



3. NOSTOCHOPSIS Wood (1869). 



1. N. lobatus Wood in Proc. Amer. Phil. Soc. Philadelphia, 127 

 <1869) ; in Smithson. Contrib. Knowl. (1874), iii. 45, t. iii. f. 6 ; 

 Born et Flah., I.e., 80 (1887) ; W. et G. S. West in Journ. Bot. 

 1897, p. 264. 



GoLUNGO Alto. — Ad rupes inundatas in rivulo Muria pr. Muria 

 sparsius ; Sept. 1854. No. 201. 



The examples of this are very fine, and agree well with the figure 

 given by Wille (in Bihang t. K. Sv. Vet.-Akad. Handl. Bd. 8, no. 18, 

 t. i. f. 1-19), with the exception of the cell-walls ; portions only were 

 as moniliform as the previously-found African examples. (Of. W. et 

 G. S. West in Journ. Bot. 1896, 381, t. 361, f. 1-2). 



The cell-walls are very thin indeed, not any more appreciable than 

 the cell- walls in the ordinary vegetative cells of a Nostoc. The majority 

 of the heterocysts are lateral, globose, and either sessile or stalked 

 (usually supported on one or two cells) ; sometimes they are intercalary, 

 and then they are always elliptic-oblong. 



XVII. SCYTONEMACE^. 



1. SCYTONEMA Ag. (1824). 



1. S. cincinnatum Thur. in Ann. Sci. Nat. 6'^ serie^ Bot. i. 380 

 (1875) ; Born et Flah., I.e., 89 (1887). 



Calothrix lanata Kiitz. Algar. Aq. Dale. Dec. I. no. 5 (1833). 



Var. aethiopicum W. et G. S. West in Journ. Bot. 1897, p. 264. 



PuNGO Andongo. — Alga nigrescens, lubrica, tenax, rhizomata 

 Xyridearum aliarumque plant, palustrium, in spongiosis crescentium, 

 crassis membranis obducens, matricibus tenaciter adhjerens — sicque 

 imprimis loca spongiosa formans. Cum Dichotviche gy2)!iophila et 

 Mougeotia irregular i in pascuis spongiosis breviter graminosis juxta 

 rupes gig. Prtesidii prope Catete ; May 1857. No. 111. 



2. S. rivulare Borzi in Nuovo Giornale Bot. Ital. xi. 373 (1879) 

 Born, et Flah. I.e., 91 (1887); W. et G. S. West, I.e. 



PuNGO Andongo. — Ad muscos rupestres rivulos crescentes perrepens, 

 in Mimosarum sylvis pr. Pedras de Guinga ; Jan. 1857. No. 13. 



Stratum golden-brown or violet ; branches rather scarce, usually 

 solitary, short, a little narrower than the primary filaments ; cells 

 sometimes a little longer than the diameter ; sheaths constantly 

 asperulate. 



This is a most interesting species, having been previously seen only 

 from Italy by its original describer. 



3. S. Arcangelii Born, et Flah., I.e., 92 (1887) ; W. et G. S. 

 West in Journ. Bot. 1897, p. 265. 



GoLUNGO Alto. — Ad muscos prope fontem magn. ad Banza de 

 Sobato de Bango sitam ; Sept. 1855. No. 159. 



